It is rectangular, roughly three metres long and one and a half metres wide, with a decorated face that tilts gently northward and protrudes only slightly above the surrounding soil. What was once carved or pecked into it is now very faint, worn by exposure to a degree that requires patience and the right light to read at all. Yet six distinct features survive, and the stone sits within clear view of the Behy River valley, enclosed on the southern and western sides by a horseshoe of mountains.

Rock art of this kind, where prehistoric people used stone tools to peck or pick repeated marks into exposed rock surfaces, is found across Atlantic Europe, with notable concentrations in the uplands of Ireland. The motifs at Kealduff follow patterns typical of the tradition. Along the north-east side of the decorated surface runs a linear arrangement of pickmarks, about 64 centimetres long, which trails off at its southern end into nine or ten small individual pockmarks. Adjacent to the west is a cup-and-ring motif, the most recognisable form in Irish rock art, consisting of a shallow central cup surrounded by two concentric rings, the whole about 13 centimetres across. Elsewhere on the stone there are further linear formations of pickmarks, a slightly curving short line that crosses a natural step in the rock, and at the southern end, both a square depression measuring 6.5 centimetres on each side and a single cupmark about 6 centimetres in diameter. A second decorated stone lies approximately 14 metres to the north-east, suggesting this was not an isolated act of marking but part of a broader, deliberate use of this particular stretch of hillside.

The decorated surface is described as very weathered and the motifs as faint, so visiting in low, raking light, either early morning or late afternoon, gives the best chance of making out the carvings. The stone itself protrudes only marginally above ground level, so it is easily overlooked underfoot in the heath vegetation.